Collecting and distributing ring for rotary electric machine stator

ABSTRACT

A collection-distribution ring comprises three busbars, each having a circular ring shape, which are integrally connected together with prescribed distances therebetween by an insulating resin. Coil connection terminals project inwardly in a radial direction and are alternately arranged in relation to the three busbars. External terminals project outwardly in the radial direction and are arranged to adjoin together at the prescribed position. These terminals are all exposed from surfaces of the insulating resin. A stator comprises the prescribed number of stator units that are arranged in a circumferential direction and are assembled together with the collection-distribution ring. Each stator unit comprises a core unit realizing magnetic teeth, an insulating member, and a coil. An outer terminal member electrically connects a first end of the coil and the coil connection terminal, and an inner terminal member provides electrical connections between second ends of the adjacent coils.

TECHNICAL FIELD

[0001] This invention relates to collection-distribution rings for usein stators of rotating electrical machines such as motors andgenerators.

BACKGROUND ART

[0002] Japanese Unexamined Patent Publication No. 2001-25187 discloses aconventional example of a stator for use in a rotating electricalmachine such as a motor and a generator. This stator comprises a statorcore having a circular ring shape, magnetic teeth wound by coils, amidpoint busbar, and collection-distribution busbars. Specifically, thestator core has a laminated or stacked structure consisting of multiplesheets of magnetic steel. The magnetic teeth are arranged around thestator core in the circumferential direction with prescribed distancestherebetween and are each projected inwardly in the radial direction,wherein the magnetic teeth are respectively wound by coils viainsulating members. The midpoint busbar is a conductive member having aring-sheet like shape, which connects together all the innercircumferential ends of the coils. The collection-distribution busbarscorrespond to three conduction members each having a ring-sheet likeshape, each of which connects together the outer circumferential ends ofevery three coils arranged in the circumferential direction.

[0003]FIG. 7 shows an example of the exterior appearance of a singlecollection-distribution busbar. That is, the collection-distributionbusbar 30 comprises a ring sheet 30 a, an external terminal 30 b, andcoil terminals 30 c. The external terminal 30 b projects outwardly inthe radial direction from the ring sheet 30 a and is connected with anexternal device such as a power source (not shown). The coil terminals30 c project inwardly in the radial direction from the ring sheet 30 a,wherein each coil terminal 30 c is connected with an outer end of a coilwound about three magnetic teeth arranged in the circumferentialdirection. In the collection-distribution busbar 30, the overall area ofthe ring sheet 30 a is coated with insulating paint, which is shown bydashed lines P in FIG. 7. In contrast, the external terminal 30 b andcoil terminals 30 c are not coated with insulating paint, so that theyare exposed from the coated surfaces of the ring sheet 30 a.

[0004]FIG. 8 shows an example of a stator 37 of a rotating electricalmachine, in which the prescribed number of stator cores 31 are arrangedin the circumferential direction along with the ring sheet 30 a of thecollection-distribution busbar 30. Each stator core 31 provides aninsulating member 33 having an extended portion 33 a, which is extendedoutwardly in the radial direction. In addition, a coil 32 having twoends 32 a and 32 b is wound about magnetic teeth 31 a via the insulatingmember 33. Each stator core 31 also provides a terminal member 34 havingtwo connecting portions 34 a and 34 b. Herein, the first end 32 a of thecoil is fixed to the extending portion 33 a of the insulating member 33via the first connecting portion 34 a of the terminal member 34. Thesecond end 34 b of the terminal member 34 fixes the position of the coilterminal 30 c, which projects inwardly in the radial direction from thering sheet 30 a of the collection-distribution busbar 30 (see dashedlines in FIG. 8). When the rotating electrical machine is designed as amotor, electric power of a power source (not shown) is transmitted tothe collection-distribution busbar 30 via the external terminal 30 b. Inaddition, electric power is distributed to the coils 32 via the terminalmembers 34, which are fixed onto the extending portions 33 a of theinsulating members 33.

[0005] A midpoint busbar 35 having a ring-sheet like shape is arrangedinside of the ring sheet 30 a of the collection-distribution busbar 30.The midpoint busbar 35 has the prescribed number of midpoint connectionterminals 35 a that project outwardly in the radial direction from themidpoint busbar 35 and are sequentially arranged with prescribed pitchestherebetween, which are equivalent to pitches of arrangements of themagnetic teeth 31 a in the stator cores 31. All the inner ends of thecoils 32 are connected together by the midpoint connection terminals 35a. FIG. 9 is an enlarged view of the selected part of FIG. 8 encompassedby a dashed circle. Each insulating member 33 for the magnetic teeth 31has a second extending portion 33 b, which is extended inwardly in theradial direction. A terminal member 36 having two connecting portions 36a and 36 b is attached to the second extending portion 33 b of theinsulating member 33. Herein, the second end 32 b of the coil 32 isfixed to the second extending portion 33 b of the insulating member 33via the first connecting portion 36 a of the terminal member 36. Inaddition, the second connecting portion 36 b of the terminal member 36fixes the position of the midpoint connection terminal 35 a, whichprojects outwardly in the radial direction from the outer circumferenceof the midpoint busbar 35. Thus, the midpoint busbar 35 mutuallyconnects together all the inner ends 32 b of the coils 32. That is, themidpoint busbar 35 forms a comprehensive midpoint for all the coils 32.

[0006] However, the aforementioned stator 37 has the following problems.

[0007] (1) Due to the prescribed positional relationships establishedbetween the external terminal 30 b and the coil terminals 30 c, thethree collection-distribution busbars 30 cannot mutually share partsthereof. That is, different sets of parts should be required withrespect to different busbars respectively. The three external terminals30 b of the three collection-distribution busbars 30 should bepreferably arranged in proximity to each other for the purpose ofestablishing connections and wiring with the external device. Inaddition, it is difficult to use common coil terminals among the threecollection-distribution busbars 30 because the coil terminals 30 c arearranged with prescribed pitches therebetween, which are three timesgreater than pitches of arrangements of the magnetic teeth 31.

[0008] (2) The midpoint busbar 35 differs from thecollection-distribution busbar 30 in structure. Therefore, it isimpossible to provide the common structure between the midpoint busbar35 and the collection-distribution busbar 30. This inevitably increasesthe number of parts, which require a large amount of labor in assembly.In particular, the three collection-distribution busbars 30 resembleeach other in shape. Therefore, when they coexist in one place, it isdifficult for the worker to discriminate between them. This will reducethe workability in assembly.

[0009] (3) The three collection-distribution busbars 30 should beelectrically insulated from each other with respect to the coils 32,which are not mutually connected together. The conventional stator 37 isassembled in such a way that the collection-distribution busbars 30 areassembled independently, wherein insulation processes should be reliablyperformed with respect to all the collection-distribution busbars 30independently. That is, the conventional stator 37 that requiresinsulation processes independently on various components requiresnumerous steps in the manufacture of each single component. In order toensure insulation performance in a stable manner with respect to eachcomponent, it may be necessary to form uniform insulation layers bycomplicated manufacturing steps such as multilayer coating. Thisincreases the total cost of the product in manufacture.

DISCLOSURE OF INVENTION

[0010] It is an object of the invention to provide acollection-distribution ring for a stator of a rotating electricmachine, which provides noticeable improvement in assembly andremarkable reduction in the cost of manufacture of the product.

[0011] A collection-distribution ring of this invention comprises threebusbars, each having a circular ring shape, that are integrallyconnected together with prescribed distances therebetween by aninsulating resin. Herein, coil connection terminals project inwardly ina radial direction from the busbars, wherein they are alternatelyarranged in relation to the three busbars and are exposed from theinsulating resin. In addition, external terminals project outwardly inthe radial direction from the busbars, wherein they are arranged toadjoin together at the prescribed position and are exposed from theinsulating resin.

[0012] A stator for use in a rotating electrical machine comprises theprescribed number of stator units that are arranged in a circumferentialdirection and are assembled together with the aforementionedcollection-distribution ring. Each stator unit comprises a core unit ofstacked magnetic metal sheets and realizing magnetic teeth, aninsulating member, and a coil. The coil is wound about the core unit viathe insulating member. In addition, each stator unit arranges an outerterminal member that electrically connects a first end of the coil woundabout the magnetic teeth and the coil connection terminal projectinginwardly from the busbar. Further, each stator unit arranges an innerterminal member that electrically connects a second end of the coilwound about the magnetic teeth and a second end of the other adjacentcoil wound about the other adjacent magnetic teeth.

[0013] Therefore, the second ends of the coils wound about the magneticteeth, which are arranged in the circumferential direction, are mutuallyconnected together, thus realizing functions of a midpoint busbar. Thatis, the collection-distribution ring eliminates the midpoint busbar bymerely connecting together the second ends of the coils by the innerterminal members.

[0014] In short, the collection-distribution ring of this inventionimproves the insulation performance between the busbars that arereliably insulated from each other by the insulating resin and areintegrally combined together, which contributes to an improvement inproductivity. In addition, it eliminates the midpoint busbar, which isconventionally required, to reduce the total weight thereof.

BRIEF DESCRIPTION OF DRAWINGS

[0015]FIG. 1 is a front view showing a collection-distribution ringcomprising three busbars and a resin (not shown) in accordance with afirst embodiment of the invention;

[0016]FIG. 2 is vertical sectional view showing selected parts of thecollection-distribution ring whose busbars are held in a rail;

[0017]FIG. 3 is a front view showing a stator of a rotating electricalmachine equipped with the collection-distribution ring shown in FIG. 1;

[0018]FIG. 4 is an enlarged view magnifying a selected area ‘A’ of thestator shown in FIG. 3;

[0019]FIG. 5 is a front view showing a single stator unit havingterminal members and a coil wound about a stator core of stackedmagnetic steel sheets;

[0020]FIG. 6 is a front view showing selected parts of a stator of arotating electrical machine in accordance with a second embodiment ofthe invention;

[0021]FIG. 7 is a front view showing a conventional example of acollection-distribution busbar for use in a stator of a rotatingelectrical machine;

[0022]FIG. 8 is a front view showing a conventional example of a statorof a rotating electrical machine equipped with a singlecollection-distribution busbar shown in FIG. 7; and

[0023]FIG. 9 is an enlarged view magnifying a selected area B of thestator shown in FIG. 8.

BEST MODE FOR CARRYING OUT THE INVENTION

[0024] This invention will be described in further detail by way ofexamples with reference to the accompanying drawings.

[0025] Now, a stator having collection-distribution rings will bedescribed in accordance with a first embodiment of the invention. FIG. 1shows a collection-distribution ring 1 for use in a three-phase rotatingelectrical machine in accordance with the first embodiment. Thecollection-distribution ring 1 comprises three busbars (or conductivemembers) 2, 3, and 4, and an insulating resin 5, wherein each busbar ismade by curving or bending a conductive sheet material having asheet-band shape into roughly a cylinder-like shape in curling process(or round bending process). The insulating resin 5 made of an insulatingresin material is formed to wrap and integrally fix together the threebusbars 2, 3, and 4.

[0026] When the rotating electrical machine is designed as a motor, thecollection-distribution ring 1 is used for distribution of electricpower supplied from an external power source (not shown). When therotating electrical machine is designed as a generator, thecollection-distribution ring 1 is used for collection of electric powersupplied to an external device (not shown).

[0027] The busbars 2, 3, and 4 comprise cylinder sections 2 a, 3 a, and4 a, each having an imperfect cylinder-like shape, a part of which iscut out in the circumferential direction, as well as prescribed numbersof coil terminals 2 b, 3 b, and 4 b, and external terminals 2 c, 3 c,and 4 c. The coil terminals 2 b, 3 b, and 4 b are sequentially arrangedin the circumferential direction with prescribed distances therebetween,wherein each of them projects inwardly in the radial direction. Theexternal terminals 2 c, 3 c, and 4 c project outwardly in the radialdirection from prescribed positions of the busbars 2, 3, and 4respectively, wherein they are arranged to adjoin together in thecircumferential direction. The three busbars 2, 3, and 4 respectivelyprovide the three cylindrical sections 2 a, 3 a, and 4 a havingdifferent radius dimensions. When the three busbars 2, 3, and 4 areassembled together in conformity with the same center area, they arearranged concentrically with prescribed distances therebetween.

[0028] The distance between the adjacent coil terminals 2 b, 3 b, and 4b is three times greater than the distance between adjacent magneticteeth 7 of the stator 6, which will be described later. The coilterminals 2 b, 3 b, and 4 b have different lengths by which they areextended in the same depth into the hollow area formed in the threebusbars 2, 3, and 4 that are arranged concentrically. That is, the coilterminals 2 b, 3 b, and 4 b are sequentially reduced in lengths in sucha way that the coil terminal 2 b projecting inwardly from the busbar 2having the largest radius has the longest length, while the other coilterminals 3 b and 4 b projecting inwardly from the other busbars 3 and 4having smaller radiuses are sequentially reduced in lengths.

[0029] The external terminals 2 c, 3 c, and 4 c are formed at prescribedpositions of the cylinder sections 2 a, 3 a, and 4 a at which when thethree busbars 2, 3, and 4 are arranged to adjoin together withprescribed intervals of distance therebetween, pitches of arrangementsof the coil terminals 2 b, 3 b, and 4 b become identical to pitches ofarrangements of the magnetic teeth 7, which project inwardly in theradial direction of the stator 6.

[0030] The prescribed patterns realizing the busbars 2, 3, and 4 arepressed out from a single metal thin sheet and are then formed intocylinder-like shapes by curling processes. Thereafter, by effectingbending processes, the coil terminals 2 b, 3 b, and 4 b are bentinwardly in the radial direction, while the external terminals 2 c, 3 c,and 4 c are bent outwardly in the radial direction.

[0031] As shown in FIG. 1, these busbars 2, 3, and 4 are arranged tomutually adjoin together in a concentric manner with prescribedintervals of distance therebetween, wherein before assembling with astator (see dashed circles), they are integrally connected together by aresin 5, thus forming an integral conduction unit.

[0032] The three busbars 2, 3, and 4 are fixed together by the resin 5in accordance with the following steps:

[0033] First, these busbars 2, 3, and 4 are inserted into three channels8 a, 8 b, and 8 c within an insulating rail 8 having a circular ringshape as shown in FIG. 2.

[0034] At this time, the coil terminals 2 b, 3 b, and 4 b that projectinwardly in the radial direction with respect to the busbars 2, 3, and 4are arranged with different distances corresponding to prescribed anglesrealizing pitches of arrangements of the magnetic teeth 7. Thus, thecoil terminals 2 b, 3 b, and 4 b are alternately arranged withprescribed pitches therebetween, which match the pitches of arrangementsof the magnetic teeth 7, so that they project inwardly in the radialdirection with respect to the busbars 2, 3, and 4 respectively. Inaddition, the external terminals 2 c, 3 c, and 4 c are arranged tomutually adjoin together with prescribed distances therebetween withrespect to the busbars 2, 3, and 4 respectively.

[0035] The aforementioned rail 8 is made of insulating materials. Inorder to secure stable insulation performance, sufficiently high sidewalls are arranged to secure wayside distances between the busbars 2, 3,and 4, which are clearly partitioned from each other. Under thecondition where the busbars 2, 3, and 4 are respectively held in thechannels 8 a, 8 b, and 8 c of the rail 8, an insulating resin that ismelted and stored in a cavity of a metal mold (not shown) is injectedinto the rail 8 and is then hardened, thus forming the resin 5integrally fixing together the three busbars 2, 3, and 4 with differentdistances.

[0036] Thus, it is possible to reliably produce one unit of thecollection-distribution ring 1 in which the three busbars 2, 3, and 4are integrally fixed together by the resin 5. In thecollection-distribution ring 1, the three busbars 2, 3, and 4 areintegrally fixed together inside of the resin 5 having a circular ringshape in such a way that they are mutually and electrically insulatedfrom each other by the insulating rail 8 and the insulating resin. Withrespect to the busbars 2, 3, and 4, the coil terminals 2 b, 3 b, and 4 bare exposed from the surface of the resin 5 and project inwardly in theradial direction, while the external terminals 2 c, 3 c, and 4 c areexposed from the surface of the resin 5 and project outwardly in theradial direction.

[0037] The collection-distribution ring 1 of the present embodimentgreatly differs from the conventional busbar 30 having a ring sheetshape shown in FIG. 7 because the busbars 2, 3, and 4 can be producedfrom the conduction sheet material (normally, copper sheet) having aband sheet like shape by curling processes. Therefore, the yield in themanufacture using the ‘expensive’ material is improved to realize aremarkable reduction in the manufacturing cost.

[0038] In addition, it is not required to form each busbar into aperfect cylinder-like shape. In other words, the cylinder sections 2 a,3 a, and 4 a are not required to realize numerous pitches that aresubstantially three times greater than the pitches of arrangements ofthe magnetic teeth 7. In this point, the present embodiment cannoticeably conserve materials for use in manufacture. When the busbars2, 3, and 4 are each formed in an imperfect cylinder-like shape, theymay be slightly reduced in strengths. To compensate for such a smallweakness, the collection-distribution ring 1 is designed in such a waythat the busbars 2, 3, and 4 are reliably supported by the rail 8 andare integrally fixed together by being encapsulated into the resin 5.Hence, the busbars 2, 3, and 4 will not be deformed.

[0039] Since the three busbars 2, 3, and 4 are integrally fixed togetherby the resin 5, the collection-distribution ring 1 of the presentembodiment can improve the workability in assembling of the stator 6. Inthe conventional method, three busbars 30 are separated from each otherand are independently assembled together with the stator, wherein aworker is required to make distinctions between the three types ofbusbars 30 having similar shapes. In contrast, thecollection-distribution ring 1 of the present embodiment allows a workerto easily install the three busbars 2, 3, and 4 in the stator 6.

[0040] In addition, the present embodiment ensures electrical insulationin a stable manner between the three busbars 2, 3, and 4 in thecollection-distribution ring 1. The conventional method uses the threebusbars 30 that are separated from each other and are independentlysubjected to insulation processes, which are troublesome and arerelatively expensive. In contrast, the present embodiment can establishsubstantially insulated conditions between the busbars 2, 3, and 4 bythe insulating rail 8, wherein these busbars are integrally fixedtogether by the insulating resin 5, thus creating reliably insulatedconditions therebetween. Thus, it is possible to guarantee theinsulation performance in a stable manner, which brings a noticeablereduction in the manufacturing cost.

[0041] Next, a description will be given with respect to a stator 6 of arotating electrical machine equipped with the collection-distributionring 1 in accordance with the present embodiment.

[0042]FIG. 3 shows the overall mechanical construction of the stator 6equipped with the collection-distribution ring 1, wherein the prescribednumber of stator units 9 are arranged to adjoin together in thecircumferential direction. That is, the stator 6 is basically similar tothe foregoing stator 37 because both of them have a similar circularring shape. FIG. 5 shows an enlarged view of the stator unit 9, whichcomprises a core unit 10, an insulating member 11, and a coil 12. Thecore unit 10 forms a built-up iron core having stacked (or laminated)‘roughly T-shaped’ magnetic steel sheets, which comprise back yokes inthe outer circumferential side and magnetic teeth 15 projecting in theinner circumferential side. By arranging the prescribed number of coreunits 10 in the circumferential direction, it is possible to assemble astator core 13 having a circular ring shape.

[0043] Similarly, each stator unit 9 is made by stacking (or laminating)the prescribed number of magnetic steel sheets 14, around which a coil12 is wound via an insulating member 11 in the outer circumferentialside of the core unit 10 constructing the magnetic teeth 15. Therefore,the stator unit 9 of the present embodiment is basically similar to theconventional one.

[0044] Of course, the stator 6 of the present embodiment clearly differsfrom the conventional stator 37 with respect to the following points:

[0045] (a) The stator 6 uses the collection-distribution ring 1 thatintegrally fixes together the aforementioned three busbars 2, 3, and 4by the resin 5.

[0046] (b) The stator 6 does not use the midpoint busbar 35, which isused in the conventional stator 37.

[0047] With respect to the insulating member 11 that is arranged in oneterminal end of the accumulated magnetic steel sheets 14, there areprovided a pair of terminal members 16 and 17, which are connected withopposite ends of the coil 12 respectively. Specifically, the terminalmember 16 is arranged in the outer circumferential side of the statorcore 13 and is fixed to the insulating member 11 by a fixing element 16c, while the terminal member 17 is arranged in the inner circumferentialside of the stator core 13 and is fixed to the insulating member by afixing element 17 c.

[0048] The terminal member 16 has a pair of forked connecting portions16 a and 16 b, between which a conductor is sandwiched. Similarly, theterminal member 17 has a pair of forked connecting portions 17 a and 17b, between which a conductor is sandwiched. With respect to the ‘outer’terminal member 16, a first end 12 a (or a collection-distributionterminal) of the coil wound about the magnetic teeth 15 is extended inone terminal end of the stacked magnetic steel sheets 14 constructingthe magnetic teeth 15 and is held by the connecting portion 16 a. Thus,it is electrically connected with the terminal member 16 by an arbitraryconnection method such as pressed or melted bonding, and fusing.

[0049] When the collection-distribution ring 1 is arranged in the outercircumferential side of one terminal ends of the magnetic teeth 15 (seedashed circles in FIG. 3), the coil connection terminals 2 b, 3 b, and 4b that project inwardly in the radial direction from thecollection-distribution ring 1 are respectively held by the otherconnecting portions 16 b of the ‘outer’ terminal members 16 that arearranged in the circumferential direction. Herein, the terminal members16 having the same shape are arranged in the same positionalrelationships with the stator unit 9.

[0050] As described above, it is possible to simultaneously insert allthe coil connection terminals 2 b, 3 b, and 4 b, which project inwardlyfrom the collection-distribution ring 1 and are arranged in thecircumferential direction with prescribed intervals of distancetherebetween, into the connecting portions 16 b of the terminal members16 that are arranged in the circumferential direction. Herein, byelectrically connecting together the coil connection terminals 2 b, 3 b,and 4 b with the connecting portions 16 b of the terminal members 16, itis possible to reliably and independently connect together the coils 12wound about three magnetic teeth 15 with the three busbars 2, 3, and 4.

[0051] It is preferable to coat proximate areas between the coilconnection terminals 2 b, 3 b, and 4 b, and the connecting portions 16 bof the terminal members 16 with insulating resins such as siliconeresins. Thus, it is possible to increase the waterproof ability of thestator 6.

[0052] The ‘inner’ terminal members 17 have similar structures of theaforementioned ‘outer’ terminal members 16. The second end 12 b of thecoil 12 wound about the magnetic teeth 15 of the stator unit 9 isfurther extended to form a roughly U-shaped midpoint terminal portion 12c, which is extended toward one terminal end of the other magnetic teethof the adjacent stator unit. As shown in FIG. 5, an intermediate portion12 e of the U-shaped midpoint terminal portion 12 c continuouslyextending from the second end 12 b of the coil 12 wound about themagnetic teeth 15 is held by the first connecting portion 17 a of theinner terminal member 17.

[0053] As shown in FIG. 4, the second connecting portion 17 b of theinner terminal member 17 holds a tip end portion 12 d of the midpointterminal portion 12 c that is extended from the ‘adjacent’ other statorunit 9.

[0054] Specifically, the stator 6 of the present embodiment differs fromthe conventional stator 37 connected with a single midpoint busbar 35(see FIG. 8) in the following points:

[0055] (a) The inner terminal member 17 having a pair of forkedconnecting portions 17 a and 17 b is arranged in the innercircumferential side of the stator core 13 in stacked T-shaped magneticsteel sheets realizing the magnetic teeth 15, wherein the firstconnecting portion 17 a holds the intermediate portion 12 e of theU-shaped midpoint terminal portion 12 c extending from the second end 12b of the coil 12 wound about the magnetic teeth 15, so that the tip endportion 12 d of the midpoint terminal portion 12 c would be connectedwith the coil wound about the other magnetic teeth of the other‘rightside’ stator unit.

[0056] (b) The second connecting portion 17 b of the inner terminalmember 17 holds the tip end portion of the midpoint terminal portionextending from the second end of the coil wound about the other magneticteeth of the other ‘leftside’ stator unit.

[0057] Therefore, the present embodiment can eliminate the midpointbusbar 35 because of the aforementioned ‘unique’ construction of thestator unit 9 having the terminal members 16 and 17. This indicates thatthe stator 6 of the present embodiment may reduce the weightsubstantially equivalent to the weight of the midpoint busbar 35compared with the conventional stator 37. Thus, it is possible tonoticeably reduce the cost for manufacturing the stator 6 compared withthe cost required for manufacturing the conventional stator 37.

[0058] Next, a description will be given with respect to a stator 20 inaccordance with the second embodiment of the invention with reference toFIG. 6, wherein parts identical to those shown in FIGS. 3 to 5 for usein the first embodiment are designated by the same reference numerals;hence, the description thereof will be omitted as necessary.

[0059] The stator 20 of the second embodiment (see FIG. 6) differs fromthe stator 6 of the first embodiment in the following points:

[0060] (a) Stator units 21 are mutually interconnected together in sucha way that they can be adequately folded.

[0061] (b) Each stator unit 21 differs from each stator unit 9 in theshape of the midpoint terminal portion.

[0062] (c) Similar to the stator unit 9, the stator unit 21 has arrangedan outer terminal member 16 in the outer circumferential side thereof inconnection with the insulating member 11. In contrast to the stator unit9, the stator unit 21 arranges a ‘specially-designed’ inner terminalmember 22 in the inner circumferential side thereof in connection withthe insulating member 11.

[0063] The stator 20 of the second embodiment comprises the stator units21 whose core units 24 are mutually connected together by means ofhinges 23 each having a square shape. That is, the stator units 21 areformed by coating the ‘cylindrically-shaped’ insulating members 11 withresins and the like; then, the coils 12 are wound about the insultingmembers 11. FIG. 6 shows two states with respect to interconnectionsbetween adjacently arranged stator units 21. At first, the adjacentstator units 21 may be mutually separated from each other but areinterconnected together by means of the hinge 23, which is shown in theleftside area of FIG. 6. Then, the stator units 21 are moved in thecircumferential direction while folded, so that the adjacent statorunits 21 are mutually brought into contact with each other, which isshown in the rightside area of FIG. 6. Thus, it is possible to arrangeall the stator units 21 mutually interconnected together by the hinges23, thus completely forming a stator 20 having a circular ring shape.Similar to the stator 6 of the first embodiment, the first end 12 a ofthe coil 12 is held by the outer terminal member 16. In addition, thesecond end (12 b) of the coil 12 wound about the stator core (13) havingthe magnetic teeth 15 is extended horizontally towards one terminal endof the other magnetic teeth of the other stator core arranged in theright side. That is, the midpoint terminal portion 12 b extending fromthe second end (12 b) of the coil 12 is formed roughly in an L-shape andis further extended rightwards in FIG. 6.

[0064] The inner terminal member 22 has a pair of connecting portions 22a and 22 b. The first connecting portion 22 a holds the intermediateportion 12 e of the ‘L-shaped’ midpoint terminal portion 12 b extendingfrom the second end (12 b) of the coil 12 wound about the stator unit21, while the second connecting portion 22 b holds the tip end portion12 d of the midpoint terminal portion 12 b of the coil 12 that isextended from and wound about the leftward adjacent stator unit 21. Inthe terminal member 22, the second connecting portion 22 b is separatedfrom the first connecting portion 22 a and is accompanied with a guideportion 22 c for guiding the tip end portion 12 d of the midpointterminal portion 12 b extended from the leftside therefor.

[0065] The function of the first connecting portion 22 a of the terminalmember 22 may be similar to that of the first connecting portion 17 a ofthe terminal member 17 arranged for the stator unit 9 of the stator 6 ofthe first embodiment. In contrast, the second connecting portion 22 b isarranged to be directed substantially perpendicular to the firstconnecting portion 22 a. In addition, the guide portion 22 c is openedand arranged to conform with the input side of the second connectingportion 22 b. FIG. 6 shows an example of the guide portion 22 c whoseopening width is gradually decreased towards the input side of thesecond connecting portion 22 b. In other words, the guide portion 22 chas a wide opening portion 22 d that is directed towards the otherstator unit 21 arranged in the leftside.

[0066] As described above, the stator 20 of the second embodiment isformed and formed by the following steps:

[0067] (a) The magnetic teeth 15 are covered with the insulating member11, about which the coil 12 is wound. The stator units 21 are assembledtogether and folded via the hinges 23, so that the stator 20 having acircular ring shape is completely formed by interconnecting together thestator units 21 in the circumferential direction.

[0068] (b) In the above, the stator units 21 are assembled together insuch a way that the tip end 12 d of the midpoint terminal portion 12 bof the coil 12 extended from the inner circumferential side of onestator unit 21 is inserted into the opening 22 d of the guide portion 22c of the other ‘adjacent’ stator unit 21; then, the stator units 21 aremoved in the circumferential direction. Thus, the adjacent stator units21 are reliably combined together in such a way that the tip end 12 d ofthe midpoint terminal portion 12 b of the coil 12 extended from onestator unit 21 is guided by interior walls of the guide portion 22 c andis held in the second connecting portion 22 b of the inner terminalmember 22 arranged in the inner circumferential side of the other‘adjacent’ stator unit 21.

[0069] (c) After the adjacent stator units 21 are brought into contactwith each other, the tip end 12 d of the midpoint terminal portion 12 bof the coil 12 of one stator unit 21 is firmly connected together withthe second connecting portion 22 b of the inner terminal member 22 ofthe other adjacent stator unit 21 by an appropriate connection methodsuch as pressed or melted bonding, and fusing. Thus, it is possible toelectrically connect the midpoint terminal portion 12 b and itsproximate area of the coil 12 of one stator unit 21 with the midpointterminal portion 12 b and its proximate area of the coil 12 of the otheradjacent stator unit 21. By performing the aforementioned operation withrespect to all the stator units 21 arranged in the circumferentialdirection, it is possible to construct the stator 20 having a circularring shape in such a way that all the midpoint terminal portions 12 bare connected together among the stator units 21.

[0070] (d) In the above, the guide portion 22 c of the inner terminalmember 22 of one stator unit 21 guides the tip end 12 d of the midpointterminal portion 12 b, which is certainly inserted into and held in thesecond connecting portion 22 b of the inner terminal member 22 of theother adjacent stator unit 21. This greatly helps a worker to performthe connection operation with respect to the stator units 21 whenassembling the stator 20.

[0071] The embodiments of this invention are described with respect tothe stators 6 and 20 each for use in a rotating electrical machine, inwhich a rotor (not shown) is arranged oppositely with a prescribed gapin relation to the magnetic teeth 15 projecting inwardly in the radialdirection. Of course, this invention is not necessarily limited to theseembodiments. Therefore, this invention can be easily applied to theother type of the rotating electrical machine in which a hollow rotorhaving a cylinder-like shape (not shown) is arranged externally of thestator whose magnetic teeth 15 project outwardly in the radialdirection.

[0072] As described heretofore, this invention has a variety of effectsand technical features, which will be described below.

[0073] (1) Since the collection-distribution ring of this inventionfixes together multiple busbars adjoining together with prescribeddistances therebetween by an insulating resin, it is possible toremarkably improve the workability in assembling thecollection-distribution ring together with stator units arranged in thecircumferential direction. Therefore, this invention does not requiresome of the assembling processes of the conventional stator in which aworker is required to make distinctions between similar busbars (orconduction members) and is also required to assemble them togetherindependently. Therefore, this invention contributes to a noticeablereduction of the time required for the assembly of a stator. Inaddition, it is possible to reliably avoid occurrence of errors inassembly.

[0074] (2) Multiple busbars (or conduction members) are integrallycombined together by the insulating resin, which allows reliableinsulation processes simultaneously with respect to multiple busbars.Therefore, it is possible to improve the reliability in manufacture ofproducts of stators. In addition, it is possible to remarkably reducethe cost for manufacturing products of stators.

[0075] (3) Coil connection terminals are exposed from the surface of theresin and project from the inner circumferential side of thecollection-distribution ring with prescribed pitches therebetween, whichmatch pitches of arrangements of magnetic teeth. Herein, by merelyadjusting the magnetic teeth and coil connection terminals in positionsonly at a certain location, it is possible to establish prescribedpositional relationships between them along the inner circumferentialside of the stator. This guarantees easy-to-handle assembly inmanufacture of the stator.

[0076] (4) In the collection-distribution ring, the busbars areadequately connected with coils wound about magnetic teeth of statorunits, which are arranged to adjoin together in the circumferentialdirection. This guarantees the proper collection and distribution ofelectricity with respect to the coils, which are reliably insulated fromeach other. Thus, it is possible to produce a rotating electricalmachine having a relatively high reliability at a relatively low cost.

[0077] (5) This invention eliminates the necessity of arranging amidpoint busbar in the collection-distribution ring, which in turncontributes to a reduction of the total weight of a rotating electricalmachine such as a motor. Hence, it is possible to produce a motor at arelatively low cost because the collection-distribution ring of thisinvention does not require the process of producing the midpoint busbarand reduces the total cost of manufacture.

[0078] (6) The stator comprises stator units having terminal members andinsulating members, wherein the adjacent stator units are combinedtogether in such a way that a coil end extending from one stator unit isconnected with a midpoint terminal portion of the other adjacent statorunit by the terminal member and is fixed to the insulating member. Thisreliably reinforces the connection between the adjacent stator unitsassembled together in the circumferential direction of the stator.Hence, it is possible to maintain connections between stator units ofthe stator in integrity. Therefore, it is possible to produce a rotatingelectrical machine having a relatively high reliability.

[0079] (7) The inner terminal members of the stator units provide guideportions, by which the coil end extending from one stator unit isreliably and easily inserted into the terminal member of the otheradjacent stator unit. Because of the provision of the guide portions, itis possible to guarantee simple and highly efficient operations inassembling together the stator units. Thus, it is possible to improvethe productivity in manufacturing stators.

[0080] As this invention may be embodied in several forms withoutdeparting from the spirit or essential characteristics thereof, thepresent embodiments are therefore illustrative and not restrictive,since the scope of the invention is defined by the appended claimsrather than by the description preceding them, and all changes that fallwithin metes and bounds of the claims, or equivalents of such metes andbounds are therefore intended to be embraced by the claims.

1-9. (Cancelled)
 10. A stator for a rotating electrical machine,comprising: a stator core (13) having a plurality of magnetic teeth (15)that are arranged in a circumferential direction with prescribeddistances therebetween and that projects in a radial direction; and aplurality of coils (12) that are wound about the magnetic teeth of thestator core via insulating members (11), wherein each of the coils isextended to provide a terminal end (12 b, 12 c, 12 d) towards oneterminal portion of a stator core unit (9), and the terminal end of eachcoil is connected with a coil connection terminal (2 b, 3 b, 4 b) of aconduction member (2, 3, 4), and wherein the coils wound about themagnetic teeth are respectively extended to provide midpoint terminalportions (12 b) and are connected with coils of other adjoining statorunit so that the adjoining coils are mutually connected togethertherewith.
 11. The stator for a rotating electrical machine according toclaim 10, wherein the insulating members are respectively equipped withterminal members (17) that provide electrical connections betweenintermediate portions (12 e) and tip end portions (12 d) of the midpointterminal portions of the adjoining coils.
 12. The stator for a rotatingelectrical machine according to claim 11, wherein the terminal membershave guide portions (22 c) for guiding the terminal end portions of theadjoining coils.
 13. A stator for a rotating electrical machinecomprising: a collection-distribution ring (1) for the rotatingelectrical machine that performs collection and distribution ofelectricity between an external device and coils (12) wound about aplurality of magnetic teeth (15), which are arranged in acircumferential direction of a stator (6) having a circular ring shapewith prescribed distances therebetween, wherein a plurality ofconduction members (2, 3, 4) are integrally connected with prescribeddistances therebetween by an insulating resin (5) before being assembledwith the stator, thus forming an integral conduction unit, and whereineach of the conduction members of the integral conduction unit comprisesa plurality of coil connection terminals (2 b, 3 b, 4 b) and an externalterminal (2 c, 3 c, 4 c), all of which are exposed from surfaces of theinsulating resin enclosing the conduction members.
 14. The stator for arotating electrical machine according to claim 13, wherein each of theconduction members is formed by bending a conductive steel sheet havinga band-sheet like shape into roughly a cylindrical shape in such a waythat the plurality of conduction members have different radiuses incurvature respectively.
 15. The stator for a rotating electrical machineaccording to claim 13 or 14, wherein the plurality of coil connectionterminals are exposed from the insulating resin and are alternatelyarranged in the circumferential direction of the stator with prescribedpitches therebetween in correspondence with pitches for arranging themagnetic teeth.
 16. The stator for a rotating electrical machine,comprising: a collection-distribution ring (1) comprising a plurality ofbusbars (2, 3, 4), each having a circular ring shape, that areintegrally connected together with prescribed distances therebetween byan insulating resin (5), in which coil connection terminals (2 b, 3 b, 4b) project inwardly in a radial direction and are alternately arrangedin relation to the plurality of busbars, and external terminals (2 c, 3c, 4 c) project outwardly in the radial direction from the plurality ofbusbars respectively and are arranged to adjoin together, so that thecoil connection terminals and the external terminals are all exposedfrom surfaces of the insulating resin, wherein a plurality of statorunits (9) that are arranged in a circumferential direction and areassembled together with the collection-distribution ring, wherein eachstator unit comprises a core unit (10) of stacked magnetic metal sheetsrealizing magnetic teeth (15), an insulating member (11), and a coil(12), which is wound about the core unit via the insulating member, andwherein each stator unit provides an outer terminal member (16) thatelectrically connect a first end (12 a) of the coil wound about themagnetic teeth and the coil connection terminal projecting inwardly fromthe busbar, and an inner terminal member (17) that electrically connectsa second end (12 b) of the coil wound about the magnetic teeth and asecond end of other adjoining coil wound about other adjoining magneticteeth together.
 17. The stator for a rotating electrical machineaccording to claim 16, wherein each stator unit provides an innerterminal member (22) that electrically connects a second end (12 b) ofthe coil wound about the magnetic teeth and a second end of the otheradjoining coil that is wound about the other adjoining magnetic teethand is guided by a guide portion (22 c).